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排序方式: 共有242条查询结果,搜索用时 31 毫秒
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Vasilyeva Inga Abdusalyamova Maxsuda Makhmudov Farchod Eshov Bakhtier Kauzlarich Susan 《Journal of Thermal Analysis and Calorimetry》2019,136(2):541-548
Journal of Thermal Analysis and Calorimetry - A high sublimation rate of Yb14MnSb11 as a promising thermoelectric material at working temperatures is a critical factor for its space power... 相似文献
34.
Seven series of polyimides have been analyzed and compared with regard to the correlation between their conformational rigidity parameters, such as the Kuhn segment, the characteristic ratio, the Van der Waals volume and free volume, and some physical properties, such as glass transition temperature, dielectric permittivity, and permeability to different gases. This review concentrates on the author's own work, placed in the context of the broader field. The conformational rigidity parameters were calculated by using the Monte Carlo method, while the values of physical properties were taken from published articles. 相似文献
35.
Robert F. Roskamp Inga K. Vockenroth Dr. Nancy Eisenmenger Julia Braunagel Ingo Köper Dr. 《Chemphyschem》2008,9(13):1920-1924
Tethered bilayer lipid membranes are established as well‐suited model membrane systems adaptable to different surfaces, for example, gold and silicon. These solid supported membranes are highly flexible in their tethering and lipid parts and can thus be optimized for functional incorporation of membrane proteins. The excellent sealing properties of the tethered membranes allow incorporated ion‐channel proteins to be investigated. Preparation of ultrasmooth aluminum oxide by sputtering and synthesis of new tethering lipids with phosphonic acid anchor groups enable formation of an electrically sealing membrane on this surface. This process is monitored by electrochemical impedance spectroscopy and by surface plasmon resonance spectroscopy. High sealing performance of the membrane and functional incorporation of the ion carrier valinomycin are demonstrated. 相似文献
36.
Inga Cikotiene Erika Pudziuvelyte Algirdas Brukstus 《Journal of heterocyclic chemistry》2008,45(6):1615-1620
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The title cyclohexenone 1d undergoes photodimerization selectively at the exocyclic C?C bond to give a 1 : 1 mixture of 1,2‐dialkynyl‐1,2‐dimethylcyclobutanes 6 and 7 . On irradiation in the presence of 2,3‐dimethylbuta‐1,3‐diene, 1d affords bicyclo[8.4.0]tetradeca‐1,2,3,7‐tetraen‐11‐one 9 . This – formal – (6+4)‐cycloadduct undergoes quantitative isomerization to 3‐cycloheptadienyl‐2,5,5‐trimethylcyclohex‐2‐enone 11 on treatment with basic silica gel. 相似文献
38.
Inga M. Arkhipova Angelo Luongo 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(3):69
The effect of damping on the re-stabilization of statically unstable linear Hamiltonian systems, performed via parametric excitation, is studied. A general multi-degree-of-freedom mechanical system is considered, close to a divergence point, at which a mode is incipiently stable and n ? 1 modes are (marginally) stable. The asymptotic dynamics of system is studied via the Multiple Scale Method, which supplies amplitude modulation equations ruling the slow flow. Several resonances between the excitation and the natural frequencies, of direct 1:1, 1:2, 2:1, or sum and difference combination types, are studied. The algorithm calls for using integer or fractional asymptotic power expansions and performing nonstandard steps. It is found that a slight damping is able to increase the performances of the control system, but only far from resonance. Results relevant to a sample system are compared with numerical findings based on the Floquet theory. 相似文献
39.
Grigoraviciute I Yamauchi H Karppinen M 《Journal of the American Chemical Society》2007,129(9):2593-2596
Among high-Tc superconductive copper oxides, there have been known phases that contain fluorite-structured layers as an additional "blocking block" between adjacent CuO2 planes. Here, we report that even a phase with the CuO2 planes separated by a 12-A thick quadruple-fluorite-layer block can be synthesized in a single phase and strongly oxygenated form to exhibit superconductivity with a Tc value as high as 55 K. The new phase is the fourth member of the (Cu,Mo)Sr2(Ce,Y)sCu2O(5+2s+delta) or (Cu,Mo)-12s2 homologous series. Comparison with the previously known s = 1, 2, and 3 members of the series reveals the amazing conclusion that Tc remains essentially unaffected upon inserting additional fluorite-structured layers between the two CuO2 planes as long as the hole-doping level of the planes is kept constant. 相似文献
40.
Janka M He W Haedicke IE Fronczek FR Frontier AJ Eisenberg R 《Journal of the American Chemical Society》2006,128(16):5312-5313
The first examples of a tandem Nazarov cyclization/Michael addition process are described. The sequence is efficiently catalyzed by Ir[Me(CO)(dppe)(DIB)]2+ and occurs with high diastereoselectivity, creating three contiguous stereocenters. The mechanistic factors controlling the reactivity and diastereoselectivity are discussed. 相似文献